JP2000091614A - Solar battery module and solar battery array - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the power generation output per unit area of a solar battery module by casting direct light on the surfaces of solar battery cells while casting scattered light on the rear faces of them. SOLUTION: Direct solar light 7 incident on the surface of a solar battery module is directly cast on the surfaces of two-sided photo detective cells 2. At the same time, direct solar light 8 incident in a space between each two adjacent solar battery cells is reflected on a reflection sheet 5. A part of the reflected light is incident on the rear faces of the solar battery cells 2 and another part of the reflected light is reflected on the inside surface of a flat glass 1 on the surface and then is incident on the surfaces of the solar battery cells 2. Moreover, scattered light 9 from the rear face side of the solar battery module is incident on the rear faces of the solar battery cells 2 through openings 6 of the reflection sheet 5 which is so located as to face the rear faces of the solar battery cells 2. Thereby, the power generation output per unit area of the solar battery module can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar cell module which is a main component of a photovoltaic power generation system and a solar cell array in which a plurality of solar cell modules are arranged.

[0002]

2. Description of the Related Art Conventional solar cell modules include those using single-sided light receiving cells and those using double-sided light receiving cells. In a module using a single-sided light receiving cell, the gap between the cells is made as small as possible, direct sunlight is efficiently received by the entire module, and the module conversion efficiency is improved. In addition, using a single-sided light-receiving cell, the arrangement interval of the cells is made larger, a reflective sheet is attached to the back side of the cell, and the direct sunlight to the gap is reflected by this reflective sheet, and the solar light is guided to the cell surface. Battery modules are known. On the other hand, as a double-sided light receiving solar cell module, there are a solar cell module having a structure sandwiched between two flat glass plates, and a solar cell module having a structure in which a cell is attached to the flat glass plate and the cell is protected by a transparent back sheet.

At present, most of the solar cells used are of the silicon crystal type, and there are also thin film type batteries such as silicon / amorphous type. However, a silicon crystal solar cell module is expensive because the silicon substrate accounts for a large proportion of the manufacturing cost.

[0004]

The conventional solar cell module as described above has a small power generation output per unit area, and in order to obtain desired power, the module becomes large and requires a large installation area. The cost is high. Further, the use of a silicon crystal solar cell further increases the cost.

The present invention has been made in view of the above problems, and provides a small or inexpensive solar cell module.

[0006]

SUMMARY OF THE INVENTION A solar cell module according to the present invention includes a double-sided light receiving type solar cell. Then, direct light enters from the front surface of the solar cell, and scattered light enters from the back surface.

In the solar cell module according to the present invention, not only direct light but also scattered light contributes to power generation. For this reason, the power generation output per unit area of the solar cell module increases. Therefore, the size or cost of the solar cell module can be reduced.

Preferably, a light reflecting means is provided in the first region on the back surface side of the solar cell, and scattered light is made to enter from the second region on the back surface side. Thereby, the reflected light can also contribute to power generation. In addition, since the second region faces the back surface of the solar cell, scattered light can be efficiently incident on the solar cell.

In the solar cell module according to the present invention, when there are a plurality of solar cells, the solar cell module is provided in a first region located between the adjacent plural solar cells on each back surface side of each solar cell. A scattered light is incident from a second region, which is provided with a light reflecting means and faces each back surface on each back surface side. Thereby, in each solar cell, direct light, reflected light, and scattered light all contribute to power generation. Therefore,
Since the power generation output per unit area of the solar cell module increases, the size and cost of the solar cell module can be reduced.

[0010] A more specific structure of the solar cell module according to the present invention comprises a first and a second material having a light transmitting material.
, A double-sided photovoltaic cell sandwiched between the first and second plate members, and light reflecting means provided on the surface of one of the first and second plate members. further,
On one surface of one of the first and second plate members, a light incident region to the solar cell is provided.

Further, a more specific configuration of the solar cell module according to the present invention is that, when a plurality of solar cells are provided, the surface of one of the first and second plate members is
Light reflecting means is provided between a plurality of adjacent solar cells. Further, on one surface of one of the first and second plate members, a plurality of light incident regions to these solar cells are provided.

According to each specific configuration of the solar cell module according to the present invention, the scattered light incident from the light incident area contributes to power generation. Therefore, the power generation output per unit area of the solar cell module increases, so that the size or cost of the solar cell module can be reduced.

In each of the above specific configurations, it is preferable that the light incident area faces the solar cell. According to this preferred configuration, the scattered light can be efficiently incident on the solar cell. In each of the above specific configurations, preferably, the light reflecting means is a reflection sheet, and the light incident area is an opening in the reflection sheet as the light incident area. Here, in order to make scattered light incident efficiently, the opening is preferably opposed to the solar cell. When a plurality of openings are provided, light leaked from the plurality of openings can draw a figure. That is, a solar cell module having a decorative function can be realized.

The solar cell array according to the present invention comprises a plurality of double-sided light-receiving solar cell modules, a pedestal on which the plurality of solar cell modules are mounted, and a light reflection mounted on the pedestal between a plurality of adjacent solar cell modules. Means. Since the light reflected by the light reflecting means contributes to power generation, the power generation output per unit area of the solar cell array increases. Therefore, the size or cost of the solar cell array can be reduced. Needless to say, it is preferable to use the above-described solar cell module according to the present invention as the solar cell module.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a partial cross section of a solar cell module according to an embodiment of the present invention. In this solar cell module, a plurality of silicon crystal-based double-sided light-receiving solar cells 2 are sandwiched between a front flat glass 1 and a rear flat glass that transmit light. There is a gap between two adjacent solar cells. The front and rear flat glass plates 1 and 3 and the solar cell 2 are made of a synthetic resin 4 for sealing and bonding that transmits light.
Are glued together. A reflection sheet 5 with a V-groove is bonded to the outer surface of the rear flat glass 3. The reflection sheet 5 has an opening 6 in a portion facing the back surface of each solar cell 2 (the back surface of the direct sunlight receiving surface). The opening 6 has substantially the same shape (rectangular shape in this embodiment) and area as the solar cell 2, and in the plane of the reflection sheet 5,
It is arranged so as to overlap with the back surface of solar cell 2.

In this embodiment, the direct sunlight 7 incident on the surface of the solar cell module is
Incident on the surface of. Direct sunlight 8 entering a gap between two adjacent solar cells is reflected by the reflection sheet 5, a part of the sunlight 8 enters the back surface of the solar cell 2, and another part of the front flat glass 1. Solar cell 2 reflected on internal surface
Incident on the surface of. Further, the scattered light 9 from the rear surface side of the solar cell module is transmitted through the opening 6 of the reflection sheet 5 provided opposite to the rear surface of the solar cell 2.
Incident on the back surface of.

In this embodiment, as described above, not only the sunlight directly incident on the solar cell 2 and the sunlight reflected on the reflection sheet 5 but also the scattered light from the back surface of the solar cell module. Is also focused on the solar cell. For this reason, the power generation output per solar cell, that is, the power generation output per unit area of the solar cell module is improved. Therefore, the solar cell module of the present embodiment is smaller than the conventional one for a desired total power generation output,
Lower cost.

FIG. 2 shows the appearance of the entire solar cell module of FIG. 1 as viewed from the front side. The front-side flat glass 1, the plurality of double-sided light-receiving solar cells 2, the rear-side flat glass 3, the reflection sheet 5, and the like described above are laminated. Further, the outer peripheral edges of the rectangular front and rear flat glass plates 1 and 3 are fitted and covered by the module outer frame 10.
The plurality of rectangular solar cells 2 are regularly arranged in the vertical and horizontal directions of the rectangular solar cell module. In this embodiment, the long side and the short side of each solar cell 2 are parallel to the long side and the short side of the solar cell module, respectively. A gap having a constant width is provided between adjacent solar cells in each of the vertical and horizontal directions of the solar cell module. Although omitted in the drawing, the plurality of solar cells 2 are connected in series and parallel by lead wires. The total number of solar cells, the number in series, and the number in parallel are appropriately set according to the required total power output.

FIG. 3 shows an external view of the entire surface of the solar cell module of FIGS. 1 and 2 as viewed from the back. A plurality of rectangular openings 6 are provided in the surface of the rectangular reflection sheet 5 at positions facing the respective solar cells 2. Multiple openings 6
Are arranged regularly in the vertical and horizontal directions of the rectangular solar cell module, similarly to the solar cell 2. Also,
The long side and the short side of each opening 6 are respectively
Are parallel to the long side and the short side. Each opening 6 is provided in a region that does not affect the reflection and light collection function of the reflection sheet 5. In the present embodiment, the long side and the short side of the opening 6 are shorter than the long side and the short side of the solar cell, respectively, so that the opening 6 is completely included in the back surface of the solar cell 2. , So that the reflection / condensing function is not impaired.

By the shape and arrangement of the solar cells 2 and the openings 6 as shown in FIGS. 2 and 3, a small solar cell module can be obtained.

In the above embodiment, the opening of the reflection sheet is for allowing the scattered light from the back side of the solar cell module to enter the solar cell. Use of such scattered light is particularly effective in the case of a solar cell module of a gantry installation type or the like. When the solar cell module of the present embodiment is used as a wall material integrated type of a building or the like,
Part of the sunlight entering from the front side leaks into the building through the opening 6. This leaked sunlight can illuminate the interior of the building.

FIG. 4 shows the appearance of the entire back surface of a solar cell module according to another embodiment of the present invention. This figure shows a solar cell module which is a wall material integrated type of a building or the like and which can draw a light pattern on the inside of the building.
The difference from the above embodiment is that the reflection sheet 5 has a plurality of opening permitting portions 11 in which openings can be appropriately provided.
Is set. The shape and arrangement of the openings are the same as those of the openings 6 in FIG. In this embodiment, a plurality of circular opening holes 12 are provided in the plurality of opening permitting portions 11 as openings. The plurality of opening holes 12 draw a desired figure pattern. Inside the building, a figure pattern is drawn by sunlight leaking from the opening hole 12. That is, the solar module of the present embodiment has a function of an upholstery.

FIG. 5 shows a solar cell array mounted on a gantry according to another embodiment of the present invention. The gantry 18 is fixedly installed on a gantry foundation 19. The double-sided light receiving solar cell module 15 shown in FIGS. 1 to 3 is mounted on a gantry 18. An array in which a plurality of solar cell modules are arranged in this manner is called a solar cell array. In the present embodiment, in such a solar cell array, adjacent two
A gap is provided between the two solar cell modules. The direct sunlight 16 entering the gap is reflected by the inter-module direct light reflection mechanism 20 attached to the gantry 18 in the gap. Inter-module direct light reflection mechanism 20
Has a reflecting structure having a V-groove or the like on the light receiving surface, and efficiently reflects incident light toward the back surface of the module to condense it. The reflected sunlight is collected on the back surface of the module 15,
Contribute to power generation. Note that, similarly to the embodiment shown in FIGS. 1 to 3, the back surface scattered light 9 is also guided to the solar cell module 15 and contributes to power generation.

The solar cell array of this embodiment is shown in FIGS.
Since the solar cell module shown in (1) is used, the size and cost of the desired total power generation output can be reduced as compared with the conventional case. In addition, since the sunlight incident between the solar cell modules by the reflection mechanism 20 contributes to the power generation, the power generation output is improved accordingly.

According to each of the above embodiments, a flat-plate concentrating solar cell module and a solar cell array having about twice the converging power of the conventional configuration can be realized with the same materials and manufacturing techniques as those of the prior art. In addition, the use of the double-sided light receiving type solar cell enables the cost required for the silicon substrate of the solar cell and the cell forming process to be significantly reduced.
Further, since the amount of silicon substrate used is reduced, it is possible to contribute to shortening the energy payback time of solar power generation. In addition, since the solar cell and the electric circuit portion such as the lead wire are sealed between the two glasses, the reliability of the solar cell module and the solar cell array are improved and the life is extended as compared with the conventional products.

According to the embodiment shown in FIG. 4, the solar cell module can draw a graphic of a design desired by the user inside the building by leakage light in addition to the original power generation function. Therefore, the application of the solar cell can be expanded.

According to the embodiment shown in FIG. 5, since direct light from the front surface is guided to the back surface of the solar cell module by the reflection and condensing mechanism, a larger electric output can be generated at low cost.

The form of the entire solar cell module and the solar cell array and each part is not limited to those of the above-described embodiments, and various forms are possible. For example, instead of the flat glass in FIG. 1, another material that transmits light, such as transparent plastic, may be used. The shape of the solar cell 2 and the opening 6 may be circular. In addition, if the position of the solar cell is fixed between the flat glass plates, the sealing adhesive need not always be used. As the solar cell, not only a silicon crystalline cell but also various solar cells such as an amorphous cell can be used. In addition, when a photovoltaic cell that generates photovoltaic power is used instead of a solar cell, the same operation and effect as when a solar cell is used are produced.

[0030]

According to the present invention, the size and cost of the solar cell module and the solar cell array can be reduced. Further, since a decorative function can be added to the solar cell module, the application range of the solar cell module can be expanded.

[Brief description of the drawings]

FIG. 1 shows a partial cross section of a solar cell module according to an embodiment of the present invention.

FIG. 2 shows an appearance of the entire solar cell module of FIG. 1 as viewed from the front side.

FIG. 3 shows an appearance of the entire surface of the solar cell module of FIGS. 1 and 2 as viewed from the back side.

FIG. 4 shows the appearance of the entire back surface of a solar cell module according to another embodiment of the present invention.

FIG. 5 shows a solar cell array mounted on a gantry according to another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Front side flat glass, 2 ... Solar cell, 3 ... Back side flat glass, 4 ... Synthetic resin for sealing and bonding, 5 ... Reflective sheet, 6
... opening, 9 ... scattered light, 10 ... module outer frame, 11 ...
Opening permitting portion, 12: opening hole, 15: solar cell module, 18: mount for solar cell module, 19: base for mount, 20: direct light reflection mechanism between modules.

Claims (12)

[Claims] 1. A solar cell module comprising a double-sided light receiving type solar cell, wherein direct light enters from the front surface of the solar cell and scattered light enters from the back surface of the front surface. 2. The solar cell according to claim 1, further comprising a light reflecting means in a first area on the back side of the solar cell, wherein the scattered light is incident from a second area on the back side. And solar cell module. 3. The solar cell module according to claim 2, wherein the second region faces the back surface of the solar cell. 4. A battery comprising a plurality of double-sided light-receiving solar cells,
Direct light is incident from each surface of the plurality of solar cells, and light reflecting means is provided in a first region located between the plurality of adjacent solar cells on each back surface side of each surface, A solar cell module, wherein scattered light is incident from a second region on each of the back surfaces facing the respective back surfaces. 5. A first and second plate member having a material that transmits light, a double-sided light-receiving solar cell sandwiched between the first and second plate members, and a first and second plate member. A light reflecting means provided on one surface; and a light incident area on the solar cell on the one surface of the first and second plate members. 6. A first and second plate member having a material that transmits light, a plurality of double-sided light-receiving solar cells sandwiched between the first and second plate members, and the first and second plate members. On the surface on one side of the plate,
Light reflecting means provided between a plurality of adjacent solar cells, and a plurality of light incident regions on the plurality of solar cells on the surface of the one of the first and second plate members. A solar cell module comprising: 7. The solar cell module according to claim 5, wherein said light reflection means is a reflection sheet, and said light incident area is an opening in said reflection sheet. 8. The solar cell module according to claim 6, wherein said light reflection means is a reflection sheet, and said light incident area is a plurality of openings in said reflection sheet. 9. The solar cell module according to claim 5, wherein the light incident area faces the solar cell. 10. The solar cell module according to claim 8, wherein the light leaking from the plurality of openings draws a figure. 11. A plurality of double-sided light-receiving solar cell modules, a mount on which the plurality of solar cell modules are mounted, and light reflecting means mounted on the mount between the plurality of adjacent solar cell modules. A solar cell array, comprising: 12. A solar cell module according to claim 11, wherein the plurality of solar cell modules are the solar cell modules according to any one of claims 1 to 8.